Use the best available reloader when --reload is passed

Fixes #1422

docs/source/settings.rst

@@ -300,8 +300,8 @@ Debugging
 reload
 ~~~~~~
 
-* ``--reload RELOADER_TYPE``
+* ``--reload``
-* ``off``
+* ``False``
 
 Restart workers when code changes.
 
@@ -312,14 +312,13 @@ The reloader is incompatible with application preloading. When using a
 paste configuration be sure that the server block does not import any
 application code or the reload will not work as designed.
 
-When using this option, you can optionally specify whether you would
+The default behavior is to attempt inotify with a fallback to file
-like to use file system polling or the kernel's inotify API to watch
+system polling. Generally, inotify should be preferred if available
-for changes. Generally, inotify should be preferred if available
+because it consumes less system resources.
-because it consumes less system resources. The default behavior (auto)
-is to attempt inotify with a fallback to FS polling.
 
-Note: In order to use the inotify reloader, you must have the 'inotify'
+.. note::
-package installed.
+   In order to use the inotify reloader, you must have the ``inotify``
+   package installed.
 
 .. _spew:
 

gunicorn/config.py

@@ -496,20 +496,6 @@ def validate_hostport(val):
         raise TypeError("Value must consist of: hostname:port")
 
 
-def validate_reloader(val):
-    if val is None:
-        val = 'auto'
-
-    choices = ['auto', 'poll', 'inotify', 'off']
-
-    if val not in choices:
-        raise ConfigError(
-            'Invalid reloader type. Must be one of: %s' % choices
-        )
-
-    return val
-
-
 def get_default_config_file():
     config_path = os.path.join(os.path.abspath(os.getcwd()),
             'gunicorn.conf.py')
@@ -828,11 +814,9 @@ class Reload(Setting):
     name = "reload"
     section = 'Debugging'
     cli = ['--reload']
-    validator = validate_reloader
+    validator = validate_bool
-    const = 'auto'
+    action = 'store_true'
-    default = 'off'
+    default = False
-    meta = 'RELOADER_TYPE'
-    nargs = '?'
 
     desc = '''\
         Restart workers when code changes.
@@ -844,14 +828,13 @@ class Reload(Setting):
         paste configuration be sure that the server block does not import any
         application code or the reload will not work as designed.
 
-        When using this option, you can optionally specify whether you would
+        The default behavior is to attempt inotify with a fallback to file
-        like to use file system polling or the kernel's inotify API to watch
+        system polling. Generally, inotify should be preferred if available
-        for changes. Generally, inotify should be preferred if available
+        because it consumes less system resources.
-        because it consumes less system resources. The default behavior (auto)
-        is to attempt inotify with a fallback to FS polling.
 
-        Note: In order to use the inotify reloader, you must have the 'inotify'
+        .. note::
-        package installed.
+           In order to use the inotify reloader, you must have the ``inotify``
+           package installed.
         '''
 
 

gunicorn/workers/base.py

@@ -15,7 +15,7 @@ import traceback
 from gunicorn import six
 from gunicorn import util
 from gunicorn.workers.workertmp import WorkerTmp
-from gunicorn.reloader import preferred_reloader, Reloader, InotifyReloader
+from gunicorn.reloader import preferred_reloader
 from gunicorn.http.errors import (
     InvalidHeader, InvalidHeaderName, InvalidRequestLine, InvalidRequestMethod,
     InvalidHTTPVersion, LimitRequestLine, LimitRequestHeaders,
@@ -111,7 +111,7 @@ class Worker(object):
         self.init_signals()
 
         # start the reloader
-        if self.cfg.reload and self.cfg.reload != 'off':
+        if self.cfg.reload:
             def changed(fname):
                 self.log.info("Worker reloading: %s modified", fname)
                 self.alive = False
@@ -119,14 +119,7 @@ class Worker(object):
                 time.sleep(0.1)
                 sys.exit(0)
 
-            if self.cfg.reload == 'poll':
+            self.reloader = preferred_reloader(callback=changed)
-                reloader_cls = Reloader
-            elif self.cfg.reload == 'inotify':
-                reloader_cls = InotifyReloader
-            else:
-                reloader_cls = preferred_reloader
-
-            self.reloader = reloader_cls(callback=changed)
             self.reloader.start()
 
         self.load_wsgi()

tests/test_config.py

@@ -333,3 +333,17 @@ def test_cli_overrides_enviroment_variables_module(monkeypatch):
     with AltArgs(["prog_name", "-c", cfg_file(), "--workers", "3"]):
         app = NoConfigApp()
     assert app.cfg.workers == 3
+
+
+@pytest.mark.parametrize("options, expected", [
+    (["myapp:app"], False),
+    (["--reload", "myapp:app"], True),
+    (["--reload", "--", "myapp:app"], True),
+    (["--reload", "-w 2", "myapp:app"], True),
+])
+def test_reload(options, expected):
+    cmdline = ["prog_name"]
+    cmdline.extend(options)
+    with AltArgs(cmdline):
+        app = NoConfigApp()
+    assert app.cfg.reload == expected